Please see https://engineering.redhat.com/docbot/rhel/rhel-5-0-0/html/en-US/Services_Plan/sn-wrk-l10n.html#sn-wrk-l10n-adding-translate for how to get inhouse apps translated
The desktop-effects capplet is internationalized, and I have added it to CVSROOT/modules as explained. (Pending releng approval for compiz-...-7...) If anything else is needed let me know.